Sand trap



J. A. LUCAS Aug. 16, 1960 AND TRAP Filed Sept. 25. 1957 A-r-ro RNEY SAND TRAP John A. Lucas, Milwaukee, Wis, assignor to The Prime Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsin Filed Sept. 25, 1957, Ser. No. 686,164

2 Claims. (Cl. 29=111) This invention relates to sand traps for locomotives and the like and particularly to an improved nozzle guard therefor.

Sand trap nozzles for admitting an air blast into the hollow interior of the said sand trap body generally include a longitudinally bored body with a tube-like tip threaded in one end thereof. The nozzle body is connected to an air line and threaded into the air inlet port of the sand trap with the tip extending into the interior thereof toward the outlet leg of the trap. The nozzle (tip and body) is adjustable axially in the port to vary the amount of sand delivered to the wheels.

A nozzle guard is mounted in the inlet port adjacent the interior of the trap and has an opening therein through which the nozzle tip extends. Nozzle guards made from metal and other rigid materials often cut and score the nozzle tip as the nozzle is installed or adjusted and are eroded rapidly by the cutting action of the sand. Furthermore, the often imperfect fit of the tip in the guard will allow sand to work back between the parts and freeze them together causing the tip to unscrew from the nozzle body upon removal or adjustment thereof. Sand from the interior of the trap can flow back freely through the guard and open port when the nozzle is removed for replacement or repair causing damage to the parts when reassembled.

It is an object of this invention, therefore, to provide a nozzle guard which will not bind or cut the nozzle when rotated in the guard, will not become frozen to the nozzle tip, and is highly resistant to sand erosion for long service life.

Another object is to provide a nozzle guard which restricts the flow of sand from the interior of the trap back through the guard when the nozzle is removed.

Another object is to provide means for cleaning, collecting and draining sand from the threads of the inlet port and nozzle.

Another object is to provide means for reducing sand erosion in the outlet leg of the trap.

These objects are attained by a nozzle guard made from a resilient material which will not bind or score the nozzle when rotated therein and is highly resistant to erosion.

The resilient guard maintains a tight seal with the nozzle tip preventing sand from working back between the parts and causing them to freeze together. The wall of the cylindrically-shaped guard is tapered externally from the mounting end thereof causing the open tip to become flattened (due to the weight of the sand) when the nozzle is removed to thereby restrict the flow of sand back through the guard. The threaded shank of the nozzle body is slotted to clean and collect sand from the threaded opening in the sand trap body. The guard is countersunk at its outer end to collect sand which accumulates at the inner end of the air inlet port between the nozzle body and the nozzle guard and is drained therefrom through an opening in the sand trap Wall.

States Patent 2,949,326 Patented Aug. 16, 1960 Fig. 1 is a vertical longitudinal section through a sand trap embodying the present invention;

Fig. 2 is a fragmentary plan view of the nozzle assembly showing the clean-out slot therein; and

Fig. 3 is an end view of the nozzle shown in Fig. 2.

Referring now to the drawings, the illustrated sand trap is of the type employed on locomotives and the like having an L-shaped body 10 provided at its upper end with a flanged sand inlet port 12 adapted for connection to a flanged outlet 13 of the usual sand dome or hopper (not shown) by bolts 14. The body is provided with a clean-out port 15 normally closed by a pipe plug 16 and a sand outlet port 18 connected to a sand delivery line 19 leading to the rails. Experience has shown that most trap cutting occurs at the sand outlet port and for this reason an expendable reducer bushing 20 is provided to prolong the life of the body. Furthermore, the bushing 20 makes it possible to use a single size sand trap with delivery lines of different size.

The means by which air is directed into the hollow interior of the sand trap body to force sand through the outlet port includes a nozzle 22 threaded into an air inlet port 24. Port 24 is positioned below the sand inlet port 12 and directed toward sand outlet port 18. Encircling the outer end of port 24 and integral with the body 10 is a circular bushing 26. A drain outlet 27 is provided at the inner end of the threaded portion of port 24 to allow sand, water, etc. to be discharged as nozzle 22 is threaded into the opening.

While the nozzle may be formed as an integral member its forward portion or tip which normally extends into the interior of the body is preferably a brass pipe or tube 28 of cylindrical shape threaded into the main or body portion 30 of the nozzle. The body portion 30 of the nozzle has an externally threaded cylindrical shank 32 of greater outside diameter than tube 28 for adjustable engagement with the threaded air inlet port 24.

A clean-out slot 31 (Figs. 2 and 3) extending axially in the threaded shank 32 of nozzle body 30 is provided to capture and carry sand from the threaded port 24 as the nozzle is threaded into the sand trap body. Slot 31 cuts through the first two or three threads on shank 32 at least down to the roots. While the slot shown extends for only part of the length of the threaded shank end to slightly below the root of the threads it should be understood that a longer and deeper slot could be used.

A lock nut 34 on shank 32 locks the nozzle in a desired position When tightened against the face of bushing 26. Outwardly of the shank 32 the nozzle body is enlarged to provide a head 36 having a threaded port 38 for connection to air line 40. Nozzle body 30 has a longitudinal passageway 42 therethrough in axial alignment with port 38 and tube 28 to allow air from line 40 to be discharged into the trap by tube 28.

A nozzle guard 44 is mounted in the air inlet port 24 adjacent the interior of the trap and has an opening 46 through which nozzle tube 28 extends. Nozzle guard 44 is made from a resilient material such as molded rubber. One example of such material is synthetic rubber of the neoprene type having an approximate 40 durometer. The guard is of substantially cylindrical shape having a circular flange 48 at one end thereof seated in a groove 50 in port 24. The outer surface of the guard tapers as at 52 from a point of larger diameter adjacent the wall of the trap body to a smaller diameter at the end of the guard. The opening 46 in the guard through which tube 28 extends has an internal diameter about the same as the external diameter of the tube 28 except at its inner end where such opening is slightly smaller in diameter than the diameter of the tube. The opening 46 is countersunk at the flanged end thereof to provide a space 54 in which sand, water, etc. carried by slot 31 collects and is drained to the exterior of the trap by drain opening 27., The nozzle guard is sufliciently flexible so that it isinstalled, without the tube in place, by pressing it inwardly through the air inlet port 24 until the flange pops into the groove 59.

Axial adjustment of nozzle 22 in the trap will vary the amount of sand carried from the sand inlet 12 out through outlet leg 13. An inward adjustment causes less sand to be delivered to the wheels and an outward adjustment the opposite etfect. The resilient nozzle guard maintains a tight seal with tube 28 despite slight variations in the outside dimensions of the tube to prevent sand from working between the parts and causing them to freeze together. Therefore, when the nozzle is backed out of the trap the nozzle tube will turn in the guard and will not unscrew from the nozzle body. The resilient nozzle guard will not bind or cut tube 28 as the nozzle is rotated therein as is the case with the nozzle guards made from a more rigid material. Furthermore, the resilient nozzle guard is highly resistant to sand erosion which is particularly severe at the outer surface of tube 28 adjacent the inner wall of the trap body. A longer service life for the nozzle guard and tube results.

The tapered wall of the cylindrically shaped guard will become flattened by the weight of the sand when the nozzle is removed to restrict the flow of sand back through the guard, and thereby reduce wear at the threads due to the abrasive eifect of sand thereat. The space 54 formed by countersinking the flanged end of the guard serves to collect sand carried by clean-outslot 31 in the nozzle as it is screwed into the trap. The accumulated sand drains from the space through drain opening 27.

I claim:

1. A sand trap comprising: a trap body having a sand inlet port, a sand outlet port and an air inlet port the inside surface of which is threaded; an externally threaded nozzle threaded into said air inlet port axially thereof and extending into the interior of said sand trap; and a substantially cylindrically shaped nozzle guard of resilient material mounted in said sand trap body axially of said air inlet port and said nozzle, said guard extending into the interior of said trap body and having an axial opening therethrough in which said nozzle is rotatably mounted with the inner end of said guard stressed to provide a snug fit on said nozzle and yet permit relative rotation of the nozzle and guard with each other so that the axial position of said nozzle can be adjusted by rotation thereof, said nozzle guard which 4 extends into said trap body being tapered towards its inner end, said tapered portion of said nozzle guard lying below said sand inlet port and in unrestricted communication with said sand inlet port, the axis of which is substantially perpendicular to the axis of said nozzle guard so that when said nozzle is removed from said air inlet port the Weight of sand from said sand inlet port bearing on the tapered portion of said nozzle guard will partially close off the opening in said guard and thereby restrict the flow of sand back through the opening in said guard, said nozzle guard being further characterized by being countersunk axially at its outer end to provide a space in which sand, water, and other foreign materials can collect, said trap body having a drain passageway therein communicating at one end with said countersunk space in said guard and extending downwardly therefrom to the exterior of said sand trap.

2. A sand trap comprising, a trap body having a sand inlet port, a sand outlet port and an air inlet port the inside portion of which is threaded; an externally threaded nozzle threaded into said air inlet port axially thereof and extending into the interior of said sand trap; a substantially cylindrically shaped nozzle guard of resilient material mounted in said sand trap body axially of said air inlet port and said nozzle, said guard extending into the interior of said trap body and having an axial opening therethrough in which said nozzle is rotatably mounted with the inner end of said guard stressed to provide a snug fit on said nozzle and yet permit relative rotation of the nozzle and guard with each other so that the axial position of said nozzle can be adjusted by rotation thereof, said trap body having a drain passageway therein communicating at one end with said threaded air inlet port and extending downwardly therefrom to the exterior of said body, said externally threaded portion of said nozzle having an axially extending slot in the threaded surface thereof cutting through the leading threads thereon to capture and carry sand from the air inlet port to said drain passageway in said trap body as said nozzle is threaded into said air inlet port.

References Cited in the file of this patent UNITED STATES PATENTS 1,065,044 Hanlon June 17, 1913 1,074,207 Rogers Sept. 30, 1913 2,030,669 White Feb. 11, 1936 2,243,243 Campbell May 27, 1941 2,252,895 Miller Aug. 19, 1941 2,324,274 Baldwin July 13, 1943 

